IC cards are most commonly issued by writing an identification number or bank account number into the memory of the card. When the card is used, the identification or account number serves to verify and record a transaction using the card. In order to prevent unauthorized issuance of an IC card, the apparatus for writing the identification or account number into the memory of the IC card is typically controlled by an issuer code.
In one approach, the code is recorded in an EPROM that is fitted into a housing adapted to serve as a plug-in module received by a receptacle at the issuing station. For an IC card to be issued, the user of the issuing station must obtain the EPROM from a secured area and plug it into the receptacle. When activated, the issuing station will read the information from the EPROM and compare it with information stored in an internal memory for the purpose of determining whether a data match exists. If the information matches, the apparatus indicates to the user that it is ready to write an identification or account number into the IC card.
Essentially, the EPROM device acts as an electronic key that prevents unauthorized use of the issuing station. Although such an electronic key is more secure than a conventional mechanical key, it nevertheless is still susceptible to unauthorized use or duplication. Such unauthorized use or duplication allows the issuing apparatus to be used to issue unauthorized cards.